The invention relates to a method for diagnosing an operating state of a contactor comprising a processing unit designed to act on voltage control means. The contactor further comprises at least one actuating coil, means for measuring at least one electric characteristic of said at least one actuating coil and at least one free-wheel diode connected in parallel to said at least one actuating coil and to the means for measuring.
The invention also relates to a contactor for implementation of said method. Said contactor comprises an electromagnetic actuator having a magnetic circuit formed by a magnetic yoke and a movable ferromagnetic coil, control means, and at least one actuating coil connected to a first and second power supply terminal via said control means. A processing unit is designed to act on the voltage control means. The contactor also comprises means for measuring an electric characteristic of said actuating coil. At least one free wheel diode is connected in parallel to said at least one actuating coil and the means for measuring.